The technical field of the present invention is that of devices suspended from a carrier craft for loading objects or for embarking persons, of the pod, or basket, type, capable of deploying from a helicopter, more especially applied to the recovery of persons in danger.
When operations are carried out to free hostages or to extricate the nationals of a country from a dangerous situation, the operational involvement of a unit is subordinated to its ability to recover the equipment it uses in the operation and the civilians or military personnel, who are the subject of the intervention, whether trapped by a situation, or liable to be so shortly.
This terminal recovery stage, which is undertaken as a matter of urgency, implies a notion of speed dictated by the imminence of a direct threat to the lives of persons who are the subject or the instigators of the intervention.
Such a recovery operation can apply to civilians or military personnel, injured or otherwise, with or without equipment to be taken with them.
In this field, several designs have already been proposed.
As the recovery of persons located in areas termed xe2x80x98at riskxe2x80x99 necessitating the use of helicopters involves either the touchdown of the aircraft or the use of a winch or of the so-called xe2x80x9cclusterxe2x80x9d system.
It is sometimes impossible for the craft to touch down owing to the uneven configuration of the terrain (rocky, presence of obstacles on its surface, etc.) or to the nature of the environment (wooded, marine, etc.).
The use of a winch is restricted by its small carrying capacity and the time it takes to be implemented.
The so-called xe2x80x9cclusterxe2x80x9d system applies solely to persons equipped with a securing harness. It too takes considerable time to implement and does not permit the transport of seriously wounded persons or those having equipment.
There is also known, from document U.S. Pat. No. 4,138,077, a folding and unfolding device suspended from a helicopter to save persons or equipment. This device is transported by helicopter to the site of the rescue in folded condition. A motorised system is then used to unfold it.
In the same technical field, there is also known patent FR 2.399.855, which discloses a rescue net in the form of a cage or car, capable of being fixed to the load hook of a helicopter or to the helicopter itself.
This rescue net is composed, in particular, of a base frame and of an upper frame, each having the shape of a square, comprising, inside the frames and laterally therebetween, flat, flexible tension straps of nylon or polyester, to constitute a structure in form of a car of upwardly decreasing size. In its deployed condition, each of the four sides of this car has an access opening, provided in the lateral straps, which can be closed by one of the closing flaps for safety reasons. The base frame, which is larger than the upper frame, is composed of two halves capable of pivoting towards one another in order to accommodate between them the upper frame and the lateral straps, to fold the rescue net as a whole after the fashion of a valise. This rescue net, which is transported folded on board a helicopter in a rectangular shape comparable with that of a package, deploys of its own accord when it is suspended from the carrying hook and released outside the helicopter.
This rescue net has a number of drawbacks, associated, in particular with its closed car shape when in deployed condition.
As a result of this shape, access is gained solely through the four lateral openings, after unfastening the flaps that close these openings. The speed of intervention is thus reduced owing to the time taken to unfasten and re-fasten all these flaps.
One major drawback of this rescue net is related to the difficulties of access, the latter being conditioned by the size of the lateral openings, as well as to the limited stowing capacity, given the restricted surface area of the base frame.
When folded, it also has the drawback of remaining relatively bulky.
A further drawback is that it is impossible to control the moment of its deployment after it has left the helicopter, which is particularly disadvantageous owing to the possible wind resistance of the deployed net, during operations taking place under adverse weather conditions.
The object of the present invention is to overcome the above drawbacks by providing a device for recovering equipment and/or persons from a carrier craft, in particular a helicopter, that is very easy and swift to implement.
The present invention also aims to provide a device permitting simple, swift access for able-bodied or injured persons, including their intervention equipment (weapons, for example) or emergency equipment (medical equipment), this being possible whatever their dimensions.
A further object of the invention is to design a device of minimum overall dimensions when in folded condition, to facilitate its transport on board a helicopter.
Another object is to permit also the triggering of the deployment or opening of a part of the device, at the moment intended.
For this purpose, the invention provides a device suspended from a carrier craft for the recovery of persons or items of equipment, of the type comprising a connection joining the craft to a foldable and deployable pod formed by a framework associated with a flexible support. The framework includes, fixed to the connection, a central mast connected to mobile means bearing the flexible support.
The central mast includes two telescopic members, one being fixed and secured by one of its ends to the connection, and the other, connected to the mobile means, being constituted by a tube sliding longitudinally about the fixed member, to ensure the folding and deployment of the mobile means and of the flexible support about the central mast.
The mobile means include, preferably, arms and stays, mutually articulated by one of their ends, with their other ends also being articulated, respectively, with the lower part and the upper part of the tube.
Each stay can be composed of two halves which can pivot towards one another in the direction of the central mast.
Preferably, the flexible support of the deployed pod is composed of at least three triangular members that are juxtaposed and rendered integral with at least three arms, with pod as a whole, folded and deployed, taking, respectively, the shape of an inverted umbrella, closed and opened.
It can comprise a bell member, constituted by a piece in the form of an inverted U rendered integral, in its centre, with the upper end of the fixed member of the mast, to hold the upper ends of the mobile means of the framework in place when the pod is folded.
It can also comprise means for locking and unlocking the upper end of the tube with the bell member, composed of at least a lock co-operating with a fastening end piece, fixed to the upper end of the tube and to the lower part of the bell member, respectively, with each lock comprising a spring associated with a ball housed in a groove in the fastening end piece to lock the pod.
The connection between craft and the pod can be constituted by an eye bolt fixed to the upper end of the fixed member of the mast.
According to one preferred form of embodiment, unlocking is triggered automatically from the helicopter by blocking the descent of a cable fastened to the eye bolt.
The pod can comprise a conical shaped steadying net disposed between the lower part of the bell member and the upper part of each stay.
Each triangular member, constituting the flexible support, can be constituted by a narrow-mesh net of synthetic material formed of flat, flexible straps sewn together.
This device has the advantage of permitting very swift recovery of civilians or military personnel, whether injured or otherwise, having equipment with them or not, and whose lives are directly threatened, or liable to be so imminently.
Another advantage resides in the original open inverted umbrella shape of the deployed pod, permitting unlimited access all around the pod, which makes for very considerable time saving during the intervention.
In folded configuration, the device also has the advantage of being very easy to stow on board an aircraft as it takes up very little room, thus not affecting the flying performance of the craft up to the recovery site.
After being dropped from the aircraft, this device advantageously affords very little wind resistance, when in folded position.
There is also a further advantage in the total control over the time of opening of the pod in relation to the conditions of the intervention.
Further characteristics and advantages of the invention will emerge from the non-limitative, detailed description given below.